chore(deps): update dependency pyarrow to v21

| datasource | package | from   | to     |
| ---------- | ------- | ------ | ------ |
| pypi       | pyarrow | 19.0.1 | 21.0.0 |

Author: dreadnode-renovate-bot[bot]

poetry.lock

@@ -53,7 +53,7 @@ dev = [
     "types-requests>=2.32.0.20250306",
     "typer>=0.15.2,<1.0.0",
     "datasets>=3.5.0,<4.0.0",
-    "pyarrow>=19.0.1,<20.0.0",
+    "pyarrow>=21.0.0,<21.1.0",
     "markdown>=3.8.2,<4.0.0",
     "markdownify>=1.1.0,<2.0.0",
     "mkdocstrings-python>=1.16.12,<2.0.0",